Great flood and aeroallergen sensitization in children with asthma and/or allergic rhinitis.

BACKGROUND: Flooding may affect aeroallergen sensitization. OBJECTIVE: To evaluate aeroallergen sensitization in children with asthma and/or allergic rhinitis (AR) by skin prick test (SPT) before and after the great flood of 2011 in Bangkok, Thailand. METHODS: The study was performed retrospectively in asthma and/or AR children (aged 0-18 years) in Siriraj Hospital, Bangkok, Thailand from 2009 to 2013. All of the cases received SPT with common aeroallergens. RESULTS: SPTs were performed from 2009-2013 in a total of 2,010 asthma and/or AR children and 58.2% and 60.5% showed positive results, respectively. Poly-sensitization to aeroallergens was found in 67.5% of asthma and 67.0% of AR SPT-positive patients. In the study period, Dermatophagoides pteronyssinus (Dp) and Dermatophagoides ferinae (Df) were the most common causes of aeroallergen sensitization (82.4% and 76.5%, respectively), followed by American cockroach (43.5%). After the severe flood in Bangkok in 2011, the trend of sensitization to American cockroach, Bermuda grass, Johnson grass, and Cladosporium spp. significantly decreased. However, the trend of sensitization to dog and Alterneria allergens in 2010 studied cases, significantly increased. During the study period, mean wheal diameter (MWD) of dog SPT was significantly associated with asthma severity, while the MWD of Dp SPT was significantly associated with AR severity. CONCLUSIONS: The aeroallergen sensitizations patterns had changed from previous years compared to the year during or after the flood. Thus, the great flood may have had a major impact on types of sensitization and the clinical patterns of airway allergy. Further confirmed by a prospective study is warranted.

Acute respiratory failure and active bleeding are the important fatality predictive factors for severe dengue viral infection.

OBJECTIVE: To determine the outcome of severe dengue viral infection (DVI) and the main dengue fatality risk factors. STUDY DESIGN: The medical records of patients aged <15 years admitted to Songklanagarind Hospital in southern Thailand during 1989-2011 were reviewed. Patients who had dengue hemorrhagic fever (DHF) grades III-IV, organ failure (cardiovascular, respiratory, liver, renal or hematologic), impaired consciousness, or aspartate aminotransferase more than 1,000 units/L, were classified as having severe DVI. To determine the fatality risk factors of severe DVI, the classification trees were constructed based on manual recursive partitioning. RESULTS: Of the 238 children with severe DVI, 30 (12.6%) died. Compared to the non-fatal DVI cases, the fatal cases had higher rates of DHF grade IV (96.7% vs 24.5%), repeated shock (93.3% vs 27.9%), acute respiratory failure (ARF) (100% vs 6.7%), acute liver failure (ALF) (96.6% vs 6.3%), acute kidney injury (AKI) (79.3% vs 4.5%), and active bleeding requiring blood transfusion (93.3% vs 5.4%), all p<0.01. The combined risk factors of ARF and active bleeding considered together predicted fatal outcome with sensitivity, specificity, and negative and positive predictive values of 0.93 (0.78-0.99), 0.97 (0.93-0.99), 0.99 (0.97-1.00), and 0.82 (0.65-0.93), respectively. The likelihood ratios for a fatal outcome in the patients who had and did not have this risk combination were 32.4 (14.6-71.7) and 0.07 (0.02-0.26), respectively. CONCLUSION: Severe DVI patients who have ARF and active bleeding are at a high risk of death, while patients without these things together should survive.